Orbital debris is an increasing concern to all satellite operations due to the effects of high velocity collisions which range from minor to catastrophic. More than twenty thousand Earth orbiting objects are currently catalogued and tracked. Most of the tracked objects are larger than ˜1-10 cm, since the smaller objects are increasingly hard to detect. However, even objects of 1 cm in size and smaller can inflict serious damage to operational satellites, since relative speeds of several kilometers per second are typical for orbital collisions. For comparison, the speed of a 22 caliber bullet leaving the barrel of a gun is about 0.3 km/s.
Collisions with large objects can currently be predicted albeit with significant uncertainties. On the other hand, the increasing number of small objects in orbit, originating from satellite collisions and anti-satellite events as well as other current space activities, is a growing concern. The number of these small objects is expected to increase into the 100 thousands, which makes then very difficult to catalog and track, especially since they are hard to detect. Collisions with small orbit debris are responsible for effects ranging from the continuous degradation of satellite performance (e.g. solar cells) to the instant damage of vital satellite components. The unambiguous attribution of such anomalies to small debris collisions is currently very difficult.
The current densities of objects in Earth orbit might in some altitude regions have even surpassed a critical value, which would soon cause a run-away chain reaction in which the creation of debris will occur faster than the removal of the debris due to the natural orbital drag. In that scenario (Kessler syndrome), all operational satellites in these particular orbit regions would turn into debris within months or years.
Several mitigations for the debris problem have been proposed and some of them are already operational. To protect spacecraft, debris shields can be used. These are particularly effective for very small debris (micron size, micrometeorites). Improved shield designs have also been proposed. However, some parts of spacecraft are hard to shield, like solar panels or optical apertures. Maneuvers to avoid collisions are possible for spacecraft that have on-board propulsion, if a likely collision is anticipated early enough.
In this environment of increasing small orbital debris, it is desirable to provide an approach to improve debris detection and anomoly attribution.